Damage won't occur under 1.3v from this sort of OC unless it MASSIVELY overheats. OCing is a process, not trial and error. Nor is it a good idea to just set voltage and multiplier and go. Besides, 1.2V will not be enough for 4.5GHz.
Here is a guide and a simplified process.
http://www.thinkcomputers.org/intel-ivy-bridge-overclocking-guide/
OK there is a guide, its not really for beginners, so it boils down to...
1. Disable all power saving adn turbo boost features and pick a load calibration, 1 being very stiff and one voltage constantly, 2 being a little more relax(easier to achieve stability), i prefer level 2.
2. Set voltage to fixed at first and drop it to 0.9v. (You can do this with stock cooling as it reduces heat...